This invention relates to pour spouts for containers of fluid, and more particularly to pour spouts which permit transfers of fluid (liquid) based on the influence of gravity at multiple flow rates, and without the risk of spills or overflow, and also to adapters that can be affixed to pour spouts for desirous results.
It is desirable to avoid overfilling of fuel to internal combustion engines in lawnmowers, tractors, personal water craft, chain saws and power tools, outboard motors, ATV recreational vehicles and even automobiles. Spilled fuel presents health and safety risks to people and the environment in general. As a result, many states have now passed environmental legislation which regulates pour spouts which can be used in conjunction with volatile fuels and other liquids.
The opportunity for spills have various causes. First, often times the gas tanks in the aforementioned internal combustion engines have very narrow openings which requires precise pouring and/or a facilitating pour spout or funnel to prevent spills.
Many times spills occur because the operator of the pour spout does not know when the receiving vessel is full. In these cases, overflows occur before pouring can be terminated.
Yet another cause of spills is the ineffective venting of the container from which the fluid is being transferred. The result of ineffective venting is an uneven fluid flow, and even in some cases surging of the fluid. Surges can cause splashing and an uneven flow makes it extremely difficult to predict fluid levels in the receiving vessel.
Another problem encountered by gravity influenced pour spouts is airlock caused by improper venting. Airlock occurs as a result of improper venting in combination with specific volume and viscosity parameters of the fluid being transferred. Such a condition can result in fluid which will not pour even when the container is inverted. This problem, while annoying, can normally be resolved by turning the container right side up again. However, this only increases the opportunity for spills.
Examples of prior spill-proof pour spouts include U.S. Pat. Nos. 4,598,743, 4,834,151, 5,076,333, 5,249,611, 5,419,378, 5,704,408, and 5,762,117. These pour spouts all have at least the following drawbacks: they do not provide multiple flow rate options and they do not provide childproof locks.
Additionally, known pour spouts are limited in their compatibility with multiple vessel types, especially in light of certain state regulations requiring specific spout diameters for certain applications. One example is the State of California, which requires a spout diameter of 1 inch. This poses a problem if one desires to use the same spout for filling a fuel tank of an automobile, the fuel tank receptacle of which has a standard size opening of ¾ inch.
The present invention addresses these problems, as well as many other problems.